Because
plants are nearly ubiquitous and keystone elements in most ecosystems,
scientists have long envisioned using them as environmental sentinels
for the sensing of stress and diseases in agricultural systems to toxic
chemicals and biological agents outside of agriculture. One way to
accomplish this would be to use unique spectral signatures from
‘native’ plants, and while spectra from vegetation tends to be messy,
progress has been made. However, as biotechnological and genomic
developments have emerged, the promise of genetically engineered
sentinel plants has emerged. There are a number of hurdles to
implementation such as problems with signal-to-noise and specificity of
outputs, but the science has progressed nonetheless. This special
issue captures the latest developments in phytosensor science and
technology and also points the way to the future. Phytosensors are
still in their infancy, and so it is exciting to witness growth and
achievements as the science breaks through various hurdles looking
toward the day when ‘talking’ plants can act as unmanned sensors to
report on crucial components in the environment.